Aeroplane.



N. CLARK & A. .E. PLANK.

AEROPLANE.

APPLICATION FILED 001". 23, 1912.

1,067,466. Patented July 15, 1913.

W5 W M ENTOR A7 v M Allomey UNITED STATES PATENT OFFICE,

NQRMAN CLARK AND ALBERT E. PLANK, 0F QUINCY, ILLINOIS.

AEROPLANE.

Specification of Letters Patent. Application filed October 23, 1912.

Serial No. 727,370.

an aeroplane in which the head atmosphericresistance is minimized.

Another ob]ect thereof 1s to produce 1n an aeroplane means for automatically maintaining the stability and equilibrium there-- of in accord with varying degrees of speed and atmospheric density and to avoid head or forward diving.

A. further object. of our invention is to produce an aeroplane in which the lower surface is formed of a series of curves from front to rear by which the frictional resistance of the atmosphere is neutralized and the horizontal equilibrium of the plane maintained, and a still-further object thereof is to provide a more simple and efficient aero-. plane than has heretofore been produced.

To these ends, our invention includes the combination and arrangement of component parts .to be hereinafter described and more particularly pointed out in the claim.

In the accompanying drawings in whichv like reference characters indicate slmilar parts, Figure 1 is a perspective view of an aeroplane of ourinvention, and Fig. 2 is a sectional .view of one of the supporting planes. In said drawings, our invention has been illustrated in a biplane, in which 1 indicates the upperplane and 2 the lower plane, which are provided with a propeller shaft 4- driving motor 5,. and controlling mechanism of conventional form. As the special design or construction of said' driving and controlling mechanism forms no part of our invention they will not be described with particularity. a

- The upper and lower planes or either of them as preferred are formed of two surfaces, the top 6 which is fiat and unbroken, and the bottom 7, which as shown is formed resists and prevents the planes in flight, and the counter-balancing of a series of curvesfrom front to rear.

The lower faces 7, form an acute angle with Patented July 15, 19 13.

front edge 8 of the top face, and thence forma curve arc A approximately two-thirds the length of the plane from frontto rear, when thesurface dips into a concave arc B of greater radius than that of the are A to the edge of the. plane. The top and bottom faces are supported in relative positions by the braces or studs 9. v

The top surfaces ofthe planes being flat offer no resistance, while in flight but the convex curve A o f-,the lower faces when driven against the air, 'forces the air downward along the convex face, and tends to. hold the nose of the plane elevated. After'passing the lower edge of the convex arc,-th e air rushes into the vacuum within the concave curve B, of the lower faces of the curved surface thus pressing against the reverse are C and imparting a forward impulse and neutralizing the head resistance of the plane.

The planes thus described may be counter balanced by weights to overcome the tendency to throw the head 'up, and'it will be appreciated that the cushion or billow of air formed by the convex arc of the lane dipping o the agencies force the plane forward and create an automatic equilibrium making volplaning or gliding in a horizontal direction possible with established and natural stability.

' Having thus described our invention, what we claim as new and desire to be secured by Letters Patent, is-

An aeroplane having a plane flat top surface and jacent to the front edge and extending back beyond the'middle of the. body of the plane almost to its rear, and reversing into a concave surface adjacent to the rear, substantially as described.

NORMAN CLARK. ALBERT E. PLANK.

a convex-curved lower surface ad- 

